Attachment for drills



June 26, 1945. G. D. PQRTER ET Al. 2,379,182

ATTACHMENT FOR DRILLS Filed July 3, 1944 B Y l QW ATTORNEY Patented June 26, 1945 UNITED STATES Pxrlfzly'r OFFICE ATTACHMENT FOR DRILLS Gerald D. Porter and Herman B. Whittington,

. Portland, Oreg.

Application July 3, 1944, Serial No. 543.298

' (ci. 71-55I 2 Claims.

This invention relates generally to devices for drilling and particularly to an attachment for drills. f

The main object of this invention is to provide an attachment for manually fed drills whereby the bit will be prevented from sticking and catching, causing undesirable action.

The second object is to provide a drill attachment which will expedite the drilling of holes through plates, the advantages being most apparent where the work is inclined somewhat with relation to the drill, in which case one side of the bit breaks through the work rst and catches on a ridge of material, inclines through the hole pulling the entire drill with it away from whatever means is employed to feed it.

These and other objects will become more apparent in the following specication as illustrated in the accompanying drawing in which:

Fig. 1 is a partial vertical section through the device.

Fig. 2 is a plan showing the portion broken away in horizontal section. W

Fig. 3 is a bottom View of an auxiliary attachment.

Similar numbers refer to similar parts throughout the several views.

Referring in detail to the drawing, there is shown a common form of manually fed power driven drill I whose drill bit II in this instance is to drill a hole through the inclined plate I2. The drill I I is relatively large compared with the plate I2 and it is well known that in such cases a drill is apt to break through on one side with bad results.

Referring in particular to my device, same will be seen to consist of a bracket I 3 having an opening Ill at one end adapted to receive the neck I5 of the drill I0 which may be secured thereto by means of the set screws I5. The bracket I3 is provided with a threaded opening I1 through which extends asthreaded sleeve I8 within whose central opening `|9 is disposed a compression spring 2|). Within the opening I9 is placed a tubular piston 2| which bears against the spring 2|! and has contained therein a rod 22 which is slidable within the piston 2| but can be clamped in any desired position by means of the set screw brought nearer to the drill bit Il which is often times found desirable.

A gland nut 29 is placed on the lower end of the sleeve I8 and prevents the escape of the piston 2|. Handles 30 project from the upper end 3| of the sleeve I8 and aiord an easy means of rotating same.

In the operation of the drill, which it will be understood is in most cases driven by power but is fed manually usually by means of a pry, the rod 22 or 28 is set by means of the set screw 23 or 32 so that it will be slightly back of the point 33 of the drill bit II. As the drilling proceeds, the piston 2| compresses the spring 20 so that by the time the bit I is near the danger point, thatl is when it is breaking through on one side of the hole, the spring 20 is resisting materially the feeding action and prevents the drill bit from spiraling through the badly formed hole in the work I2.

We claim:

1. In a device of the class described, the combination of an elongated bracket having means for attaching one end of same to a power drill and having a threaded opening at the other end thereof, a threaded sleeve extending downwardly through said opening in parallelism with the axis of the drill bit, a compression spring mounted in said sleeve, a tubular piston below said spring, a

rod adjustably mounted in said tubular piston,v

connected to said piston and adjustable with relation to the point of the drill bit whereby one end of said rod will engage the work behind the point of said bit and whereby the drilling of a hole will cause said rod to compress said spring and offer a spring resistance to the feeding action of the drill.

GERALD D. PORTER. HERMAN B. WHITTINGTON. 

